Refrigerating apparatus



Dec. 11, 192s.

A. -M. THOMSON REFRIGERATING APPARATUS 3 Sheets-Sheet 1 Original Filed Oct. 20, 1926 .qzjiwlfg;

ATTORNEY5 Dec. 11, 1928.

- A. M. THOMSON REFRIGERATING APPARATUS Original Filed Oct. 20, 1926 5 Sheets-Sheet 2 INVENTOR ATTORNEYS 5 Sheets-Sheet :5

A. M. THOMSON REFRIGERATING APPARATUS Original Filed Oct. 20, 1925 Dec. 11, 1928.

, m. J z b MH w w a {M 1 a Z z N ENTOR ATTORNEYS Patented Dec. 11, 19280 UNITED STATES 1,694,630 PATENT OFFICE.

ALFRED MORRIS THOMSON, OF NEWARK, NEW JERSEY, ASSIGNOR TO JOSEPH MEROAIDALNTE, OF NEW YORK, N. Y.

REFRIGEEATING APPARATUS.

Original application filed October 20, 1926, Serial No. 142,846. Divided and this application filed Kay 12, 1927. Serial No. 190,743.

This invention relates to refrigerating ap paratus and particularly to refrigerating apparatus of the compression type. One of the objects of the inventions is to provide an efficient refrigeration system having the various parts arranged in a compact form and constructed in such a manner that the parts can be readily assembled; and so that the system will require little or no attention after it is installed.

Refrigeration systems of the compression type include a refrigerating element located in a cooling chamber and supplied with a liquid refrigerant which upon changing to the gaseous state within the cooling element, produces the desired coolingefli'ect. The system includes a pum or compressor for compressing the gasified refrigerant, a condenser for cooling and liquefying the compressed refrigerant, and an expansion valve through which the refrigerant passes to the refri crating element. A rotary pump is suita le asa means for compressing the gasifled refrigerant. Where such a pump is used, it is necessary to provide a sealing fluid for the pump. It is desirable tocool this sealing fluid in order to prevent particles thereof from being carried over into the condenser and ultimately into the refrigeration element, and one obJect of my invention is to provide improved means for cooling this sealing fluid.

My invention contemplates the provision.

of an improved casing for a rotary pump or compressor, provjsion being made for cooling the sealing fluid within the casing. In general, this is accomplished by providing one or more air passages extendin r through the casing and providing suitab e means, such as a fan, for causing air to flow through the passages. I prefer to employ a condenser comprising two parts located near each side of the pump casing, the arrangementbeing such that a single fan can be used for the purpose of causing air to flow against the condenser and through the passages in the pump casing. A motor is provi ed for driving the pump, and the fan can be located on the motor shaft or so as to be driven by this shaft. The expansion valve of the system is preferably located at one side of the motor and a valve manifold for servicing the system and controlling the flow of the refrigerant can be located on the other side of the motor. The various parts can thus be arranged in a minimum of space without rendering any of the parts inaccessible in the event that repairs are necessary.

This application is a division of my copending application, Serial No. 142,846, filed October 20, 1926.

The various objects and advantages of my invention, some of which have been mentioned above, may be best understood by considering the following detailed description, which is to be taken in conjunction with the accompanying drawings illustrating one embodiment of my invention. In the accompanying drawings,

Fig. 1 is a plan view of a refrigerating apparatus constructed in accordance with my invention;

Fig. 2 is an elevation, partly in section, of the apparatus shown in Fig. 1;

Fig. 3 is a vertical section view taken on line 3-3 of Fig. 2, showing details of construction; and

Fig. 4 is a vertical section View of a check valve forming part of the system shown in Figs. 1, 2 and 3.

In the accompanying drawings, I have illustrated a compressor or pump casing'l, enclosing a rotary pump 2 of the gear type. The pump shaft 3 is driven by a motor 4; through a flexible coupling 5. A fan 6 is mounted on the motor shaft and is adapted to produce a current of air directed against a condenser 7 and against the casing 1. A pipe 8 connects the upper part of the condenser with the interior of the casing 1 through a valve 9 carried by a closure plate 10 covering an opening in the top of this casing. The rotary. pump 2 is carried by a closure plate 11 covering an opening in the side of the casing near the top thereof. A gasified refrigerant such as sulfur dioxide is supplied to the pump through a pipe 12 which communicates with the pump through the closure plate 11. The pipe 12 communicates with a valve manifold 13 which in turn communicates with a pipe 14 leading from the refrigeration element (not shown). The compressed refrigerant, after being liquefied Within the condenser 7, passes through the pipe 15 to a float valve 16. After passing through this valve, the refrigerant is conducted to the refrigeration element through the pipe 17. Y

The gasified refrigerant returning from the refrigeration element flows through pipe 14, manifold-13, pipe 12, to the pump 2, which compresses it and discharges it into the pump casing 1. The compressed refrigerant then passes through the pipe 8 into the condenser 7, then through pipe 15 to the expansion valve '16, and back to the refrigeration element through the pipe 17.

The condenser preferably consists of two vertically arranged coils located near each side of the pump casing 1 and interconnected, at the top by means of a pipe 18 and at the bottom by means of a pipe 19. These coils are preferably provided with heat radiating fins which serve to increase the radiating surfaces. The fan 6 is preferably constructed so as to produce a diverging current of air, and inasmuch as the condenser coils are located near the sides of the casing 1, the air which comes in contact with the coils does notthereafter come in contact with the casing, It is desirable to have air at atmospheric temperature come in contact with the casing rather than air which has been heated by coming in contact with the condenser coils.

My improved pump casing 1 comprises a casting having an opening in the side thereof near the top covered by the closure plate 11 and having 'a second opening in the top of the casing covered by the closure plate 10. One or more tubular members 20 are provided in the casing near the bottom thereof and preferably integral with the casing. These members form air passages extending through the casing and arranged in such a manner that some of the air set in motion by the fan 6 passes through these members, thus cooling the contents of the casing. This cooling feature is provided primarily for the purpose of cooling the sealing fluid for the rotary pump, but it will be understood that the compressed gas within the casing is also cooled to some extent by the air passing through these tubular members.

The tubular members 20 within the casing 1 are preferably formed in such a manner that the diameter-at some point intermediate the ends of each member is less than the diameters of the ends, thus providing a Venturi throat through which the air passes. This serves tocause the air to pass through at high velocity and this increases the efficiency of the air as a cooling medium, To further increase the velocity of the air and to thoroughly mix the same, I may provide a plurality of spiral battles 21 within each of the tubular members 20.

The motor 4 and the compressor casing 1 are mounted on-a suitable support or bed plate 22, and I prefer to mount the casing 1 in such a manner that it is spaced apart from the surface of the bed plate in order to permit the air to pass beneath the casing to cool the bottom of the same. In order to increase this cooling effect, I may provide a plurality of ribs 23 along the bottom of the casing. The tubular members 20 are preferably spaced ilbOWi the bottom of the inside of the casing, and the oil which collects in the bottom of the casing is cooled not only by the air passing through the members 20, but also by the air passing underneath the casing. A pipe 2% dips into the oil in the bottom of the casing 1 and .serves to deliver the oil to the intake side of the rotary pump.

Any suitable pump can be used for the purpose of compressing the refrigerant, but I prefer to use a rotary pump such as that described in the Groh Patent N 0. 1,495,411. I have found that where a pump of this type is employed, it is desirable to provide some means for preventing motor action of the pump. When the motor 4 stops, there is a tendency for the pump 2 to act as a motor and operate backwards due to the high pressure of the refrigerant within the casing 1. In order to prevent this action, the result of which would be to permit the compressed refrigerant to escape into the pipe 12, I prefer to provide a check valve such as that illustrated in detail in Fig. 4. This valve comprises a movable valve member 25, cooperating with a valve seat 26 and arranged so that under normal operation of the system, the partial vacuum created by the pump is sufficient to cause the refrigerant in the ipe 12 to lift the valve and permit the refiigerant to escape past the valve and into the pump. When the pump stops,

however, the valve closes and prevents or limits motor action of the pump.

The pump 2 and the tubular members 20 are arranged within the casing 1 in such a manner that the sealing fluid discharged from the pump comes in contact with these members and the sealing fluid is thereby cooled. In order to compel the oil to come directly in contact with the members 20 instead of a portion of it flowing down the side of the casing 1, I prefer to provide one or more baflie or rib members 27, preferably integral with the casing and projecting in toward the center of the casing.

I have provided a pair of pet-cocks 28 and 29 on one side of the casing 1, which serve as a means for ascertaining the level of the sealing fluid within the casing. These pet-cocks are arranged at different levels and the casing is normally supplied with sufficient oil so that the level of this liquid is near the upper pet-cock. If at any time {it is found that the level is not high enough so that the oil will flow out of the lower petcock, then oil can be supplied to the system until there is sufiicient oil so that some of it will flow out of the upper pet-cock. These pet-cocks are of course closed during the normal operation of the system.

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'10 comprises a threade It is desirable to provide some means for filtering the compressed refrigerant before it leaves the casing 1, thus preventing small globules or particles of oil from passing through the pipe 8 into the condenser 7. To accomplish this result, I have provided a screening device 30 consisting of a plprality of concentrically arranged tubular screens and carried b the closure plate 10. The parts are pre erably so arranged'that this screening device is on the side of the pump remote from the point of discharge from the pump.

The valve 9 carried b the closure plate valve member 31 having a double valve head cooperating with a valve seat 32 formed in the closure plate 10, and with the threaded end of a plug 33 which carries the valve member. The plug 33 has a screw-threaded connection with the cover plate 10 and it is adapted to receive packing 34 held in place by a packing ring 35, The outer end of the valve member 31 is adapted to receive a wrench, and this end of the member is normally enclosed within the plug members 33 by a cap 36. The construction and arrangement of the valve is such that during normal operation of the system, the valve head is closed against the end of the plug 33, thus preventing the re frigerant from passing along the screwthreads toward t e packing 34. The valve member can be moved to its other extreme position whenever it is necessary to prevent the refrigerant from. flowing into the 'condenser 7.

Any suitable valve manifold can be used for the purpose of supplying refrigerant and sealing fluid to the system or discharg-.

ing the refrigerant and sealing fluid from the system, but I prefer to use a valve manifold of the type shown in the accompanying drawings and described and claimed in my co-pending application, Serial No. 143,289 filed October 21L 1926. This valve manifold, indicated by the reference character 13, comprises a casting having lateral passages and a transverse connection 37 interconnecting the lateral passages. Afilling port is arranged in one side of the casting, preferably in line with the transverse connection 37, this port being normally closed by a plug 38. alves 39 and 40 control the communication between the port above mentioned and the two lateral assages extending through the manifold. imilar valves 40 and 41 control the flOW of refrigerant through the valve manifold, valve 40 being arranged to control the flow through pipe 12 and valve 41 controlling the flow through pipe 15.

Any suitable expansion valve may be employed, but I prefer to use an expansion valve ofvthe type illustrated in the accompanying drawings and described and claimed in my co-pending application, Serial No.

149,844 filed November 22, 1926. This valve is of the float typeand comprises a float chamber communicating with the valve manifold 13 -b means of the pipe 15. When the level 0 the liquid refrigerant in the float chamber rises to a certain point, the float valve opens to permit some of the refrigerant to escape into the pipe 17 leading to the. refrigeration element. The liquid flows through pipe 17 and ultimately changes to the gaseous state within .the refrigeration element. A pet-cock 42 may be provided near the top of the float chamber. This serves as a means for withdrawing any air trapped in the system while it is being charged, and for withdrawing from the system any non-condensable gases which may be formed therein.

The float valve 16 and the valve manifold 13 are preferably arranged on opposite sides of the driving motor 4, and the fan 6 is preferably arranged between the motor and the pump casing 1, with the condenser coils arranged near the fan and near the sides of the pump casing 1. -With the parts arranged in this manner, they are readily accessible for making repairs, and the apparatus can be assembled with the minimum of labor. The ap aratus occupies a very small space, thus ma ing it particularly suitable for domestic refrigeration purposes. It is not necessary to have any cooling apparatus for the sealing fluid arranged on the outside of the compressor casing, and the construction and arrangement of parts is suchthat the cooling air is used in a very eflicient manner. I

It is to be understood that the invention is not limited to the particularembodiment illustrated and described, but includes such modifications thereof as fall within the scope of the'appended claims.

I claim;

1. In a refrigerating apparatus, the combination of a gas-tight casing having an air passage extending therethrough, a rotary pump in said casing for compressing the gasified refrigerant, means for operating the pump, and means for causing air to flow through the said passage.

2. In a refrigerating apparatus, the combination of a gas-tight casing adapted to hold oil and having an air passage extending therethrough, a rotary pump in said casing for compressing a gasified refrigerant, means for operating the pump, and means for causing air to flow through the said passage to cool the oil in said casing.

3. -In a refrigerating apparatus, the combination of a gas-tight casing adapted to hold oil and having an air passage extending therethrough, and a plurality of heat radiating ribs on the bottom thereof, a rotary pump within the casing for compressing a gas1fied refrigerant, means for operating the pump, and means for causing. air to flow through the said passage and along the ribs on the casing to cool the oil in said casing.

4. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member within the casing forming an air passage extending therethrough, and means for causing air to flow through said passage, the said member being arranged so that the sealing oil discharged from the pump comes in contact with said member.

5. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member within the casing forming an air passage extending therethrough, means for causing air to flow through said passage, and means for defleeting the oil discharged from the pump onto said member.

6. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member within the casing forming an air passage extending therethrough, means for causing air to flow through said passage, and means for deflecting the oil discharged from the pump onto said member, comprising a rib member integral with the casing and projecting toward the center of the casing.

7. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member within the casing forming an air passage extending therethrough, and means for causing air to flow through said passage, the inher diameter of said member being smaller intermediate the ends thereof than the diameters of the ends of the member.

8. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member withinthe casing forming an air passage extending therethrough, and means for causing air to flow through said passage. the said member having spiral battles on the interior thereof.

9. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member Within the casing forming anair passage extending therethrough, and means for causing air to flow through said passage, the said member having spiral baffles on the interior thereof, and the inner diameter of said member being smaller intermediate the ends thereof than the diameters of the ends of said member.

10. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a tubular member within the casing forming an air passage extending therethrough, and means for causing air to flow through said passage, the said member being arranged near the bottom of the casing but spaced apart therefrom, and the bottomof the casing being p k'pvided with a plurality of heat radiating r1 s.

11. In a refrigerating apparatus, the combination of a gas-tight casing, a rotary pump therein for compressing a gasified refrigerant, sealing oil for the pump, means for operating the pump, a plurality of tubular members within the casing forming air passages extending therethrough, and a fan for causing air to flow through said passages.

12. In a refrigerating apparatus, a gas- .tight casing adapted to hold sealing oil and having an opening in one side thereof near the top of the casing, a tubular member integral with the casing forming an air passage extending therethrough, a detachable closure plate for the opening in said casing, a rotary pump supported by said closure plate, the said pump being arranged with respect to said tubular member in such a manner that sealing oil discharged from the pump comes in contact with said member.

13. In a refrigerating apparatus, a gastight casing having an opening in the side thereof near the top of the casing and having an opening in the top of the casing, a closure plate for the first mentioned opening, a rotary pump carried by said closure plate, a sealing fluid for said pump, a closure plate for the opening in the top of the casing, a fluid connection carried by the last mentioned closure plate, a screen device carried by this closure plate for preventing the sealing oil from gaining access to said fluid connection, and a valve carried by said last mentioned closure plate.

In testimony whereof I aflix my signature.

ALFRED MORRIS THOMSON. 

